As the Information and Communications Technology (ICT) industry continuously develops, performance such as a capacity and density of a product such as a router, a switch, or a server is continuously improved, and power of an entire device is continuously increasing. To meet a requirement of a large air volume for dissipating heat for a core component in the entire device, a fan speed is accordingly improved. In this way, noise generated by a fan becomes relatively large and a noise problem of the entire system is increasingly severe. Therefore, seeking a measure for effectively reducing the noise of the fan is one of urgent to-be-resolved problems in sustained development of the entire device in future.